C2H2 on addition with H2 forms ethane in presence of palladium catalyst but if reaction is carried in the presence of barium sulphate and quinoline, the product is ethene and not ethane. Why?
When using a palladium catalyst and in the presence of barium sulphide and quinidine, the addition reaction occurs in a different way. The palladium catalyst aids in the full addition of hydrogen to ethyne, resulting in the synthesis of ethane and the absence of unsaturation in the molecule. However, barium sulphide and quinidine aid in partial oxidation and just two hydrogen additions, resulting in partial hydrogenation. CH≡CH+H2−→PdCH2=CH2−→PdH2CH3−CH3 CH≡CH+H2→PdCH2=CH2→PdH2CH3−CH3 CH≡CH+H2−→−−−−−−−−BaSO4,quinolinePdCH2=CH2CH≡CH+H2→BaSO4,quinolinePdCH2=CH2
